package com.edou.base.util;

import com.alibaba.fastjson.JSONObject;
import org.bouncycastle.jce.provider.BouncyCastleProvider;
import org.bouncycastle.util.encoders.Base64;

import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import java.security.AlgorithmParameters;
import java.security.Security;
import java.util.Arrays;
/**
 * @author zhangyaofang
 * @create 2018-11-27 10:15 AM
 * @desc 微信工具类
 **/
public class WxUtils {
	static {
		Security.addProvider(new BouncyCastleProvider());
	}
	public static JSONObject getUserInfo(String encryptedData, String sessionKey, String iv){
		// 被加密的数据
		byte[] dataByte = Base64.decode(encryptedData);
		// 加密秘钥
		byte[] keyByte = Base64.decode(sessionKey);
		// 偏移量
		byte[] ivByte = Base64.decode(iv);

		try {
			// 如果密钥不足16位，那么就补足.  这个if 中的内容很重要
			int base = 16;
			if (keyByte.length % base != 0) {
				int groups = keyByte.length / base + (keyByte.length % base != 0 ? 1 : 0);
				byte[] temp = new byte[groups * base];
				Arrays.fill(temp, (byte) 0);
				System.arraycopy(keyByte, 0, temp, 0, keyByte.length);
				keyByte = temp;
			}
			// 初始化
			Cipher cipher = Cipher.getInstance("AES/CBC/PKCS7Padding","BC");
			SecretKeySpec spec = new SecretKeySpec(keyByte, "AES");
			AlgorithmParameters parameters = AlgorithmParameters.getInstance("AES");
			parameters.init(new IvParameterSpec(ivByte));
			// 初始化
			cipher.init(Cipher.DECRYPT_MODE, spec, parameters);
			byte[] resultByte = cipher.doFinal(dataByte);
			if (null != resultByte && resultByte.length > 0) {
				String result = new String(resultByte, "UTF-8");
				return JSONObject.parseObject(result);
			}
		} catch (Exception e) {
			e.printStackTrace();
		}
		return null;
	}


	public static void main(String[] args) throws Exception {
		// 需要加密的字串 //
		String appId = "wx939dfc2e2b5dc6ce";
		String sessionKey = "qp6gI0XrYpGLjfzbQcZi2w==";
		String encryptedData ="CoecauqAWpZZFhs3GPHvsMEr7yY23n4Vw0g+mJQoeVec2cjXdpeMewFFV1XIeDzCEpKxeGTgmqGMhNWpGgfFEZ+LDZf8az3ORySjsb/rZxAv1i7vDiSvfRKMwIawpQ6lMCRkD8EmqPnyCgNgTObaILW2Retx049PdjYcG4v+iEOyJ/QhvfP/kCX6MGqG/WzHyL4sp3qX/rXySKyfSwCPnM5k7QkcwRRFwrsMUuwI9W/3YS3Q7n7mFgQOXLsGpPLpHfzxrWXTNqKljEE5NufJ5QfNV4fWb6gDwRB3gORaB0VU/GkhNZX2yBK/3SNQg/heZlOoY1hmt+aXYFlpDaAi5Iiujmt2nocDazoQ5/yF7UKPQ/cOV9f8CE+J+c5sEFNu7HpGBNCe2IHGkF5U6B4uZfyQQDwLgxI88fDkRvXCwri8mfm4615uDalQqS7ucvCsX0hyR1MDOBfiXWUXzZs/Jg==";
		String iv = "ILQ3WnIgMzJfKVBp9MaX9A==";
		JSONObject jsonObject = WxUtils.getUserInfo(encryptedData, sessionKey, iv);
		System.out.println(jsonObject);
	}



}

